"in reaper its still destructive editing if i save the rpp right ? which is like rb seq. in reaps i still have to save previous versions if i want to go back right ?"
Reaper uses all the source files direct and keeps them intact when saving to rpp, there is no destruction, no matter how many edits you can go back to the original file, it's unharmed.
That's why a RealBand seq of 1.3gb of Biab RTs RDs is only a 2meg saved project file in Reaper (rpp). there is no creation of any new files. Why create copies to fill up the hard drive when you can use the files direct without harming them in any way ? Biab don't create any wav files when it generates, it saves all the wav instruction in a small frozen SGU 1.5meg not 1.3gig seq of wav files. I remember Noah used destructive editing on the ark.